Physician assistants and nurse practitioners, who work in tandem with doctors to provide primary care to patients, are key to making health care reform work in Oregon.

But there aren’t enough of them in Lane County, and the shortage is projected to worsen by 2020, according to an Oregon Health Authority report.

In 2012, Lane County had about 900 full-time-­equivalent medical doctors, 150 FTE nurse practitioners and 75 FTE physician assistants — throughout the health care industry, not just in primary care, the report said…